Synthesis of diol nitrate compounds from fatty acid wastes as cetane improvers

Abstract

Glycol nitrate compounds could be prepared by nitration of fatty acid ethylene glycol ester such as soybean fatty acid waste and coconut fatty acid waste with concentrated nitric acid and concentrated sulfuric acid, while maintaining the temperature of the reaction at 0+-2 ํC in the presence of dichloromethane. The nitrate compounds obtained were identified by spectroscopic techniques, such as Infrared Spectroscopy and Nuclear Magnetic Resonance Spectroscopy. The nitrate compounds could be easily blended with base diesel fuel. They were effective in increasing cetane number to 0.5, 0.7, 2.0, 3.9, 5.6 and 7.1 units for soybean fatty acid ethylene glycol nitrate and 0.4, 0.5, 1.4, 2.7, 4.0 and 5.1 units for coconut fatty acid ethylene glycol nitrate at concentrations of 0.05%, 0.10%, 0.25%, 0.50%, 0.75% and 1.00% by weight, respectively. These synthesized nitrate compounds had potential to be used to improve cetane number of base diesel fuel.